As described in WO 2012/177337, there are two major crosslinking mechanisms for acrylic adhesives: free-radical copolymerization of multifunctional ethylenically unsaturated groups with the other monomers, and covalent or ionic crosslinking through the functional monomers, such as acrylic acid. Another method is the use of UV crosslinkers, such as copolymerizable benzophenones or post-added photocrosslinkers, such as multifunctional benzophenones and triazines. In the past, a variety of different materials have been used as crosslinking agents, e.g., polyfunctional acrylates, acetophenones, benzophenones, and triazines.
WO 2012/177337 (abstract) describes a pre-adhesive composition comprising an epoxy-functional (meth)acryloyl copolymer and epoxy resin, which when crosslinked using an ionic photoacid generator (PAG) provides a pressure-sensitive adhesive and pressure-sensitive adhesive articles having desirable properties.
WO2012/161997 (abstract) describes a pre-adhesive composition comprising an acid- and epoxy-functional (meth)acryloyl copolymer, which when crosslinked using an ionic photoacid generator (PAG) provides a pressure-sensitive adhesive and pressure-sensitive adhesive articles having desirable properties.